Piper gaudichaudianum Kunth (Piperaceae) accumulates gaudichaudianic acid, a prenylated benzopyran, as its major component. Interestingly, this trypanocidal compound occurs as a racemic mixture. Herein, transcriptomic investigations of Piper gaudichaudianum using the RNA-seq approach are reported, and from the analysis of the transcripts expressed it was possible to propose a complete biosynthetic pathway for the production of gaudichaudianic acid, including the steps that originate its precursor, p-hydroxybenzoic acid. Peperomia obtusifolia (L.) A. Dietr. (Piperaceae) also accumulates racemic benzopyrans, however, its chromanes originate from the polyketide pathway, while the chromenes from Piper derives from the shikimate pathway. Recent transcriptomic and proteomic studies of the former species did not identify polyketide synthases involved in the production of the benzopyran moiety, but revealed the expression of tocopherol cyclase, which may be responsible for the cyclization of the 3,4-dihydro-2H-pyran ring. The analysis of the enzymes involved in the secondary metabolism of Piper gaudichaudianum and the comparison with the data previously obtained from Peperomia obtusifolia can provide valuable information on how these compounds are biosynthesized.

Atualmente, as plantas medicinais movem altos valores financeiros em todo o mundo e representam o tipo de tratamento mais acessível para cerca de 80% da população, principalmente entre os países em desenvolvimento. Entretanto, existe ainda uma falta de conhecimento sobre propriedades químicas, farmacológicas e toxicológicas a fim de assegurar a eficácia e segurança das plantas medicinais. Os critérios de eficácia e segurança de plantas medicinais estão relacionados a qualidade, isto é, as plantas necessitam ser corretamente identificadas, cultivadas e coletadas, devem estar livres de material estranho, partes de outras plantas e contaminações inorgânicas e/ou microbianas. O objetivo deste estudo foi o de elucidar os diferentes processos e padronizações sobre o controle de drogas vegetais, principalmente no Brasil.

Nowadays medicinal plants move high financial values at the world and represent a type of treatment more accessible for about 80% of people, mainly among developing countries. However, there is a lack of knowledge about chemical, pharmacological and toxicological properties towards ensure their efficacy and safety. Efficacy and safety criteria of medicinal plants are related to quality, that is, the plants need to be correctly identified, cultivated and harvested, they must be free of strange material, part of other plants and inorganic and/or microorganisms contamination. The aim of this study was to elucidate different process and standardizations about quality control of vegetal drugs mainly in Brazil.

No presente trabalho, foram investigadas a composição química e atividades biológicas de extratos brutos obtidos com etanol 50%, etanol 70%, acetona:água (7:3; v/v) e clorofórmio das folhas de Plinia cauliflora (DC.) Kausel, Myrtaceae, uma árvore nativa de várias regiões do Brasil. Os rastreamentos histoquímico e fitoquímico foram feitos de acordo com reações de caracterização e cromatografia em camada delgada. Para auxiliar na padronização dos extratos foram realizadas determinações do teor de fenóis totais e de flavonoides totais, espectrofotometricamente. A atividade antioxidante foi analisada pela porcentagem de sequestro de radicais livres usando solução de DPPH. A atividade antimicrobiana foi avaliada frente a bactérias patogênicas Gram-positivas, Gram-negativas e espécies de Candida utilizando os métodos de difusão em ágar e determinação da concentração inibitória mínima (MIC) de acordo com métodos padronizados. As folhas apresentaram lipídeos nas cavidades secretoras e fenóis, principalmente taninos, nas nervuras e parênquima paliçádico. Os extratos polares apresentaram flavonoides, taninos, alto teor de fenóis totais e de flavonoides totais. Os extratos mostraram elevada atividade antioxidante e a atividade antimicrobiana foi melhor contra as espécies de Candida do que contra as bactérias.

In this work, chemical and biological activities of crude extracts obtained with 50% ethanol, 70% ethanol, acetone:water (7:3; v/v) and chloroform of Plinia cauliflora (DC.) Kausel, Myrtaceae, leaves, a native tree from several regions of Brazil, was investigated. Histochemical and phytochemical screenings were done according to characterization reactions and thin layer chromatography. To assist in extracts standardization, total phenol and flavonoids content spectrophotometric was performed. Antioxidant activity was analyzed by percentage of radical scavenging using DPPH solution. Antimicrobial activity was evaluated against Gram-positive, Gram-negative pathogenic bacteria and species of Candida using agar diffusion and minimal inhibitory concentration (MIC) determination methods according to standard methods. The leaves presented lipids at secretory cavity and phenols, mainly tannins, in nervures and palisade parenchyma. Polar extracts showed flavonoids, tannins and high content of phenols and flavonoids. The extracts showed great antioxidant activity and antimicrobial activity was better against Candida species than against bacteria.